Human impact on Amazon Basin recently evaluated

New scientific research shows how human activity is transforming the world’s biggest land-based ecosystem

A paper published this month by the Woods Hole Research Centre in the journal Nature claims that human land use is altering water and energy cycles in the Amazon. In particular, the interplay of air coming in from the Atlantic Ocean, water transpiration by the forest, and solar radiation are all being effected and even have the potential to alter carbon storage, rainfall patterns and river discharge on a basin-wide scale.

Studying changes in greenhouse-gas emissions, and energy and water cycles, the study found signs of transition to a disturbance-dominated regime in the south and east of the Amazon basin.

“One strong sign of a new disturbance regime is the high number of recent large-scale wildfires, which are a by-product of intentional fires in Brazil’s ‘arc of deforestation,'” says co-author Jennifer K. Balch.

It appears that the expansion and intensification of agriculture, logging and urban development are beginning to stress the natural integrity of the Amazon’s ecosystem, arguably the largest and most important terrestrial ecosystem on the planet generating 20% of the world’s oxygen and also around 20% of its fresh water discharge. The Amazon forest also stores around 100 billion tones of carbon, calculated to be the equivalent of some 10 years’ worth of global fossil fuel emissions.

There have been changes in river flow and sedimentation plus clear lengthening of the dry season in the southern and eastern areas of the Basin.

“Whether similar changes are likely to occur in other parts of the basin will depend on the interplay of management decisions and the impacts of climate change during the next few years and decades,” suggests lead scientist Dr. Eric Davidson.